Vulcanization of rubber



Patented Sept. 27, 1932 UNITED ES .PA-r

is'zaoas HUGH MILLS BUNBURY AND WILLIAM JoHNson-s vrrrn;Narration,on rians rwroir,

MANCHESTER, AND WILFRED ARCHIBA-TQDSEXTONQOF HUDIDER-SEIELD}ENGLAERTD, ASSIGNORS TO IMPERIAL CHEMICAL Iimusrn-rns Iran, A CORPORATION orGREA'm;

BRITAIN VULOANIZATION OE RUBBER 1N0 Drawing. Application filed March 30, 1981, Serial; and. in Great Britain Aprfl 29,

5 accelerators may be produced by the interaction of alkali salts of mercaptoarylenethiazoles with 1-chloro-2 a-dinitro-naphthalene. We have also found that our Y new products are particularly valuable when used in conjunction with a basic organic accelerator such as, for example, diphenylguanicline.

Our new accelerators, particularly I when mixed with a basic organic accelerator, such as diphenylguanidine, possess the highly desirable property of delayed action, that, is to say, vulcanization at a low temperature, e. g. 110 0., is very slow, but at a relatively high temperature, e. g. 141 (3., proceeds with great rapidity.

Our invention may be exemplified by the following examples, it being understood that the amounts and specific ingredients mentioned in said examples are by way of illustration and not by limitation.

OaN SQ\ 7 It has a melting point at 144 C.

Example 2 0.5 parts of the product of Example 1 are incorporated into a rubber mix compound of pale crepe rubber 100 parts, zinc oxide 10 parts, barytes parts, sulphur 2.5 part-s.

0.25 parts of the product of Example 1; 5 together with 0.25 parts'of diphenylgim p dine are incorporated into a rubber mix of the composition given in Example 2. After being vulcanized .at 110 C. for 50 minutes vulcanization for 20 minutes at 141 C. gives f the rubber had a tensile strength at break of only 18 kg. per sq. cm. whereas after being vulcanized at 141 C..for only 20 minutes it had a tensile strength atbreakof persq.cm.

Various modifications of our; invention may be made Without departing 'fromthe spirit thereof. In. general, the interaction of ,1-chloro-2:t-dinitro naphthalene with an 'aryl mercapto thiazole, and particularly a soluble salt thereof, such as the'alkali metal salt, results in a compound to which. we ascribe thefollowing formula}.

In the above formula 1% represents an aromatic nucleus which may or may not be substituted. Thus, B may be a benzenering or a naphthalene ring, and elther of these rings 'may contain substituents such as the allryl groups.

While we have illustrated our invention with the use of diphenylguanidine, it is to be understood that other basic organic accelerators may be employed such as, for example, diorthotolylguanidine and various other basic accelerators now on the market.

Since many embodiments of this invention,"

differing widely in one or more respects, may be made without departing from the spirit of our invention, it is to be understood that We do not limit ourselves to the foregoing examples or description except as indicated in the following claims:

We claim: 1. A method of treating rubber which comprises adding to the rubber, prior to vulcanization, a compound formed by the reaction of 1-chlor0-2 4-dinitro-naphthalene With an aryl mercapto thiazole, and therea-fter'vulcanlzing.

2. A method of treating rubber which 'comprises adding to the rubber, prior to vulcanization, a compound formed by the reaction of '1-chloro-2:4-dinitro naphthalene .l with V mercapto benzo thia-zole, and thereafter Vulcanizmg.

3. A method of treating rubber which comprises adding to the rubber, prior to vulcanization, a diarylguanidine accelerator and a compound formed by the reaction'of l-chloro- 2: 4-dinitro-naphthalene with the sodium salt of lneroaptobenzothiazole, and thereafter vulcanizing. i

4. A method of treatingrubher whioh comprises adding to the rubber, prior to vulcaniz'ation, a diarylguanidine accelerator and a compound having the probable formula:

' in'which R is an aromatic nucleus; a-nd thereafter vulcanizing. I

5. Vulcanized rubber produced by "the method defined in Claim '6. Vulcanized rubber produced bythe method defined in claim 2. V V

7. Vulcanized rubber produced by the method defined in claim 3.

8. Vulcanized rubber produced 'by' the method defined in claim 4:,

In testimony whereof We afix our signatures.

HUGH MILLS BUNBURY. i WILLIAM JoHNsoN 51m n NAUNTON. I WILFRED Akcg ggmssxrou. 

